The present invention relates generally to umbrellas, and more particularly, is directed to an umbrella canopy and a method of forming the same.
In order for an umbrella canopy to be effective, it is necessary that water not accumulate on the upper surface of the canopy. Otherwise, the weight of the water on the umbrella will render the umbrella difficult to use and may damage the umbrella canopy. Accordingly, umbrella canopies have been provided with a downwardly bowed configuration. Thus, water which impacts on the upper surface of the umbrella canopy runs outwardly in the radial direction, and falls off of the peripheral edge thereof, thereby preventing such accumulation.
This bowed effect has been achieved in two different ways. In a first way, the canopy is manufactured from a plurality of individual segments, much like slices of a pie. Each segment is formed with convex side edges having a length greater than the peripheral edge thereof so that when the side edges of all of the segments are sewn together, a bowed effect is imparted to the canopy. However, such a canopy is complex to manufacture and adds cost to the umbrella. Examples of such canopies are found in umbrellas presently sold under the trademark "TOTES".
In a second way, the canopy is manufactured from a single punched sheet having no bowing effect imparted thereto, but having an elasticity. The bowing effect is imparted by the struts, which apply a force to the canopy so that the canopy assumes the bowed configuration. However, an umbrella using such an arrangement becomes costly and complex to manufacture because of the need for additional struts that impart such bowed configuration to the canopy. Examples of such canopies are disclosed in U.S. Pat. No. 3,844,301 to Harrell; U.S. Pat. No. 4,842,003 to Baldwin et al and U.S. Pat. No. 4,966,179 to Baldwin.